A calorimeter contains 30.0 mL of water at 13.0 °C. When 1.30 g of X (a substance
with a molar mass of 46.0 g/mol) is
added, it dissolves via the reaction
X(s) + H2O(1) X(aq)
and the temperature of the solution
increases to 28.5 °C.
Calculate the enthalpy change, AH, for
this reaction per mole of X.
Assume that the specific heat of the
resulting solution is equal to that of water
[4.18 J/(g• °C)], that density of water is
1.00 g/mL, and that no heat is lost to the
calorimeter itself, nor to the surroundings.